The Dangers of Dieting and Long-Term Weight Loss
With the debate about carbs versus fat in the fight against obesity, nutrition and cancer experts worry that dieters are ignoring good nutrition. Experts tell us that a weight loss diet and a healthful diet should be one and the same.
Spurred on by a slew of diet books, Americans are increasingly going to extremes in their approach to either carbohydrates or fats. Those in the anti-carb camp shun such nutritious foods as cereals, fruits, sweet potatoes, beans and milk. The anti-fat dieters avoid nuts, salmon, avocado, peanut butter and salad oils. Nutrition experts worry that both groups are missing vital nutrients.
The Downsides of Dieting
According to a report in Obesity Research, dieters shunning carbohydrates tend to have diets quite low in fiber and vitamins E, A, B6, thiamin and folate, as well as the minerals calcium, magnesium, iron and potassium.
Dieters with extremely low-fat diets may consume ample fruits, vegetables and whole grains, but tend to have low intakes of vitamins E and B12 and the mineral zinc.
The Key to Weight Control
Variety is key to both good health and weight control. Instead of avoiding fats altogether, experts tell us to enjoy the taste and variety of healthful fats.
The American Heart Association encourages Americans to include fats from vegetables, fish, legumes and nuts as part of a healthful diet. Some heart-healthy fats come from olive and canola oils, nuts, fatty fish and flaxseed.
When following a reduced-fat diet, the key is to limit added sugars as well. Regular sodas and jellybeans are fat free, but since they provide ample calories with little nutrition, they're often called empty calories.
"It's not just about eating low-fat foods," says Cathy Nonas, registered dietitian at North General Hospital in New York City. "It's how you put the whole diet together. It's smart to include lots of foods rich in fiber like fruits, vegetables and whole grains."
Cancer Concerns
Concern is also coming from cancer experts who see that in the quest to drop weight, many Americans are avoiding foods known to have health-enhancing properties – specifically fruits, vegetables and whole-grains.
A survey conducted for the American Institute for Cancer Research (AICR) shows that greater than three-fourths of Americans believe that to lose weight, the kind of food they eat is more important than the amount they eat.
But nutrition consultant and researcher Marjorie Freedman, Ph.D., points out that calories are the main determinant of weight loss. "All diets that reduce caloric intake result in weight loss, but it appears that only those people who continue to eat a diet low in calories, plus who exercise, are successful at long-term weight maintenance," she says.
Keeping It Off – Safely
The National Weight Control Registry tracks individuals who have lost and kept off a significant amount of weight. Researchers reported that successful long-term weight loss maintainers (those who lost an average of 66 pounds and kept it off for an average of five and a half years) generally eat a diet low in fat, monitor both their weight and their food intake and engage in high levels of regular physical activity. This is consistent with recommendations for cancer prevention as well.
The very foods avoided by many dieters are the ones rich in fiber that are clearly linked to a lower risk of colon cancer, according to the AICR. Similarly, these same foods – fruits, vegetables and whole-grains – are rich in vitamins and phytochemicals (disease-fighting compounds) linked to a lower risk of several cancers.
Ritva Butrum, vice president for research at AICR, points to documents citing thousands of studies showing a correlation between fruit and vegetable intake and a reduced cancer risk. Specifically, a 1997 AICR report estimated that 30 to 40 percent of all cancers could be prevented by changing Americans' diet and exercise habits. Furthermore, by simply eating at least five servings of fruits and vegetables daily, we could prevent at least 20 percent of all cancers, including cancers of the breast, colon, stomach, lung and esophagus.
"Today's best available science tells us what your grandmother always knew: Eat a variety of vegetables and fruits, all year round," Butrum says.
But Americans are not following this advice. The Centers for Disease Control and Prevention (CDC) tell us that only about a quarter of Americans consume the minimum recommended amount of fruits and vegetables.
The New American Plate
Instead of avoiding whole categories of food, it's prudent to enjoy moderate portions of the types of carbohydrates and fats known to be important for health.
Concerned that Americans are sacrificing long-term health for short-term weight loss, the AICR introduced "The New American Plate." This 36-page brochure tells Americans to focus on both proportion and portion to control their weight and to lower their risk of cancer.
According to the brochure, plant-based foods like vegetables, fruits, whole grains and beans should cover at least two-thirds of the plate. Fish, poultry, low-fat dairy and other animal-based foods should cover only one-third of the plate. Proportions like these help prevent cancer and other chronic diseases, researchers report.
The second emphasis is on portion. Skip super-sized meals, jumbo bagels, the second chicken breast and that third slice of pizza. To lose weight, you'll have to eat less.
The "New American Plate" brochure teaches you to eyeball your portions in accordance to the United States Department of Agriculture (USDA) standard serving sizes. A meat serving (3 ounces) is the size of a deck of cards, dried fruit (one-quarter cup) is similar in size to a golf ball and pasta (one-half cup) is equal to a half of a baseball.
In Control and Active
Donna Plymale of Virginia Beach, Va., is 22 pounds lighter without avoiding any food or category of food. During the past seven months, she's changed the way she thinks about food, learned to control portions, become very physically active and discovered the value of spending time on herself. She believes what her registered dietitian told her: that all foods can fit.
"If I want something, I just have to watch the amount," Plymale says. She recently bought several boxes of chocolate-covered peanuts because they were on sale. All went immediately into the freezer. "Now when I want them, I count out 15 at a time," she says. "That's enough of a sugar fix to last a few days. It isn't until you've been practicing portion control that you can resist the temptation of eating them just because they're there."
The trick for Plymale and so many others who are successful at weight loss seems to be allowing behavior changes to occur gradually over many weeks or months and in understanding that these changes are lifelong.
Changes for Life
Finally, in the report in Obesity Research, the authors conclude the following: "The American public needs to be told (and
believe) that diets are not followed for eight days, eight weeks or eight months,
but rather form the basis of everyday food choices throughout their lives. A diet
high in vegetables, fruits, complex carbohydrates (whole grains and legumes) and
low-fat dairy is a moderate-fat, low-calorie diet that prevents weight gain, results
in weight loss and weight maintenance. It is associated with fullness and satiety.
It reduces risk of chronic disease. It is fast, convenient and inexpensive."
- Choose a diet rich in a variety of plant-based foods.
- Eat plenty of vegetables and fruits.
- Maintain a healthy weight and be physically active.
- Drink alcohol only in moderation, if at all.
- Select foods low in fat and salt.
- Prepare and store food safely.
- Do not use tobacco in any form.
For a free copy of "The New American Plate" brochure, contact the AICR at 800-843-8114 or at www.aicr.org.




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